Gantry type hybrid parallel linkage five-axis machine tool

ABSTRACT

Disclosed herein is a gantry type hybrid parallel linkage five-axis machine tool composed of a machine framework a parallel spatial linkage mechanism, a feeding shaft mechanism, and a controller unit. The parallel spatial linkage mechanism is formed of three straight feeding molding dies rotatably hinged together with a base so that enabling this rotatable base to perform uni-dimensional linear motion and two-dimensional swiveling. Besides by controlling the operation of the feeding shaft mechanism with the controller unit, the parallel spatial linkage mechanism fixed to the machine framework is able to perform two-dimensional planar motion so as to operate the machine tools more accurately and efficiently in refining work.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a gantry type hybrid parallellinkage 5-axis machine tool, in particular, to a high efficiency machinetool having at least five dimensional axes moving direction composed ofa parallel spatial linkage mechanism and a gantry type framework.

[0003] 2. Description of the Prior Art

[0004] In bygone time, the conventional gantry type 5-axis machine toolsare all in a form of serially linked feeding mechanism in which a linearfeeding shaft and a rotating shaft are laid overlapping. Referring toFIGS. 1(A) and 1(B), wherein FIG. 1(A) is a gantry type 5-axis machinetool presently in mass production by PARPAS Co., and FIG. 1(B) shows itsmain shaft head in possession of two independently rotatabledirections(A/C axes rotational direction). This type of machine tool isthe most commonly adopted gantry type 5-axis machine tool. In thismachine tool, the X aix feeding control is carried out by movement of amain shaft head base along a transverse beam; the Y axis feeding controlis carried out by movement of the transverse beam along a U shapedstructure; While the Z axis feeding control is carried out by movementof the head base. As for the directional adjustment of the A/C axis iscontrolled by the rotatable main shaft head shown in FIG. 1(B). Hence,the scheme of the gantry type 5-axis machine tool shown in FIG. 1(A) isbasically a serially banked mechanism with rigidity like a seriallyjointed spring. In case there is a component in short of rigidity, therigidity of the whole serial system will be degraded.

[0005] Fatal shortcomings of such a serial mechanism exist in itsexcessive cantilever length that brings about too long loading path,less rigidity, susceptible to yielding to bending moment, and thetheremally non-symmetric structure which often cause restriction tosystem dynamic frequency range disadvantageous to high speed operation.Putting the structure in a rough finish condition is an usual remedy ofsolving the problem. However, the machine constructed as such requiresgreater driving force to activate the feeding mechanism resulting ingreater power consumption and increasing production cost. At present,notwithstanding the geometrical errors in machine dimension and thethermal deformation etc. can be compensated through computer numericalcontrol (CNC) technology so as to upgrade the machine accuracy for aserially constructed machine tool with such a less costy computersoftware, it is a primary consideration that whether the machine is ofsufficient repeatability, (ie having sufficient rigidity and resistiveto low thermal deformation). It is regretful that the present seriallyconstructed machine tools are far from these features.

[0006] Meanwhile, it is that one which having a main shaft head composedof two rotational axes has the lowest rigidity yet the highestproduction cost among the conventional gantry type 5-axis machine toolsthat causes the serial feeding machanism applied therefore to sufferfrom insufficient rigidity and difficulty in high speed operation.Moreover, users have to tclerate a high market price for this type ofmachine tools. It is therefore the utmost important matter to improvethe rigidity of the main shaft head of the above described 5-axismachine tool and reduce its production cost so as to promote thedomestic and even the international market growth for the gantry type5-axis machine tool.

[0007] Aiming at the above depicted problems, the present invention isto propose an ingeniously developed construction for a gantry typehybrid parallel linkage five-axis machine tool capable of operating witha satisfactory rigidity, high speed, and less thermal deformation.

SUMMARY OF THE INVENTION

[0008] Therefore, it is an object of the present invention to provide agantry type hybrid parallel linkage 5-axis machine tool wherein bycombining the parallel spatial linkage with all types of gantry machinetool so as to palliate the aforesaid defects of the conventional gantrytype multi-axis serial machine tools such as long loading path caused bya too long cantilever arm, insufficient rigidity, susceptible todeformation by bending moment, and thermally non-symmetric structure.

[0009] It is another object of the present invention to provide a gantrytype hybrid parallel linkage 5-axis machine tool with a simple structureeasy for assembling yet having a high rigidity and a low inertiasuitable for high speed feeding operation thereby upgrading the machineaccuracy and widening the system dynamic frequency region.

[0010] For achieving aforesaid objects, the gist of the presentinvention is to apply my “Hybrid structural Multi-Axis machine Tool”disclose in Patent Gazette No.363480 Taiwan ROC, and “CompositeMechanism Multi-Axis Machine Tool” disclosed in U.S. Pat. No. 6,048,143,for all types of gantry structural machine tool so as to improve theoperation speed of the feeding mechanism of the gantry type machine toolwell utilizing the high rigidity and the low inertia features of aparallel spatial linkage mechanism.

[0011] The present invention essentially comprises: A pedestal with atleast two parallel linear guide ways provided at its one surfacethereof; and a working platform with two sliding slots provide at itssurface facing to the pedestal such that the working platform may movestraightly with respect to the pedestal by coupling the two slidingslots with the two linear guide ways. A machine framework is at leastcomposed of a planar roof and two supporting columns, the end portionsof the columns are parallelly fixed to both sides of the pedestal, andthe surfaces of the other two end portions are each provided with alinear guide way. Besides, a sliding slot is formed at each side of theplanar roof such that the planar roof is able to make straight linearmotion with respect to the columns by coupling the two sliding slotswith the two linear guide ways on the end portion s of the columns. Ahollow guide hood is secured its one end to one side of the planar roof,and the other end extending towards the pedestal. A parallel spatiallinkage mechanism formed of a plurality of straight feeding molding diesare parallelly in connection with a base in the way that the individualmolding die is able to swivel freely, and that each molding die isconnected with the base in an indivisual position. By so the base isable to make at least two dimensional swiveling driven by those straightfeeding molding dies. Each straight feeding molding die includes alinear guide way, a sliding base, and a connecting rod, the sliding basecan move linearly along the linear guide way, the connecting rod can atleast make an uni-dimensional swiveling with its one end hinged to thesliding base in the version that forming a hinge pin at the rod sidewhile forming a corresponding bearing on the sliding base side such thatthe other end of the connecting rod is able to make uni-dimensionalswiveling with respect to the joint on the sliding base as a fulcrum.Besides, the opposite end of the connecting rod may be rotatably hingedto the sliding base with a universal shaft coupling or a ball joint.With this structure the sliding base is able to make at leastuni-dimensional displacement and two dimensional swiveling thusaltogether three dimensional movement is possible. A refining moldingunit is installed on a side surface of the Pedestal facing to theworking platform. The refining molding unit is a cutting equipmenthaving cutting tools Provided at its one end thereof capable of cuttingand refining a work piece gripped on the working platform. Besides, thisrefining molding unit may also be a welding or supersonic bondingequipment. A feeding shaft mechanism is for driving above mentionedplanar roof to make uni-dimensional movement along the linear guideways. A controller is for controlling and coordinating the operation ofparallel spatial linkage mechanism with the feeding shaft mechanism, andadjusting the relative position between the refining molding unit andthe working platform.

[0012] Meanwhile, in the present invention, the aspect of assembling thepedestal, the working platform, the machine framework and the guide hoodcan be varied in many respect for matching with the parallel spatiallinkage so as to serve effectively as a parallel spatial linkagemechanism. If the working platform is secured to one surface of thepedestal, and one end portion of each column is parallelly fixed to eachside of the pedestal respectively, whereas the other end portion of eachcolumn is provided with a linear guide way which is able to match itsown corresponding linear guide way so as to enable the planar roof tomake uni-dimensional movement (Y axis direction). And, other two linearguide ways are formed on the other end surfaces of both columns. Theformer two linear guide ways and the latter two linear guide waysrespectively make their projections on X ais and Y axis planesperpendicular to each other thereby guiding hood is able to makeuni-dimensional movement (X axis direction) by the two sliding slotsformed on it to slide on the two linear guide ways provided on theplanar roof. And, further modification is possible with the structurethat the two linear guide ways formed on the pedestal facing to ∩ shapedmachine framework and the two linear guide ways formed on the planarroof make projection on the XY axis planes perpendicular to each othersuch that the working platform is able to make uni-dimensional movementin X axis direction by coupling the two sliding slots formed on thebottom of the working platform with the two linear guide ways formed onthe pedestal.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] To enable a further understanding of the innovative andtechnological content of the invention herein, refer to the detaileddescription of the invention and the accompanying brief description ofthe drawings.

[0014]FIG. 1(A) is a three dimensional view of a conventional gantrytype five-axis machine tool;

[0015]FIG. 1(B) is an illustrative view of a main shaft head of aconventional gantry type five-axis machine tool;

[0016]FIG. 2 is a three dimensional view of the present invention;

[0017]FIG. 3 is a three dimensional exploded view of the presentinvention for illustration;

[0018]FIG. 4 is a three dimensional view of the parallel spatial linkagemechanism used in the present invention;

[0019]FIGS. 4A and 4B are illustrative views showing the transferringway of the feeding shaft mechanism in an embodiment of the presentinvention;

[0020]FIGS. 4C and 4D are illustrative views showing the transferringway of the straight feeding molding unit in an embodiment of the presentinvention;

[0021]FIG. 5 is an illustrative view in a second embodiment of thepresent invention;

[0022]FIG. 6 is an illustrative view in a third embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023] Referring to FIG. 2 through FIG. 4, wherein FIG. 2 is a threedimensional view of the present invention, and also is a drawing of anembodiment of the present invention. FIG. 3 is a three dimensionalexploded view of the present invention for illustration purpose, andFIG. 4 shows a three dimensional view of the parallel spatial linkagemachenism used in the present invention. In the present invention, apedestal 1 used for entraining all component parts of the presentinvention on the ground is provided, the other components are a workingplatform 2, a machine framework 3, a guide hood 4, a parallel spatiallinkage mechanism 5, a refining molding unit 6, a feeding shaftmachanism 7, and a controller 8. There are at least two parallel linearguide ways 11 provided at one surface of the pedestal 1, and two slidingslots 21 are provided at one surface of the working platform 2 facing tothe pedestal 1 such that the working platform 2 may move straightly withrespect to the pedestal 1 by coupling the two sliding slots 21 with thetwo linear guide ways 11. The machine framework 3 is composed of aplanar roof 31 and two supporting columns 32, 33. The end portions321,331 of the columns 32,33 are parallelly fixed to both sides of thepedestal 1, and the surfaces 323,333 of the other two end portions322,332 are provided with linear guide ways 324,334 respectively.Besides, sliding slots 311, 312 are formed at both sides of the planarroof 31 respectly such that the planar roof 31 is able to make straightlinear motion (Y axis direction) with respect to the columns 32,33 bycoupling the two sliding slots 311,312 with the two linear guide ways324,334 on the end portions 322,332 when the planar roof 31 is driven bythe feeding shaft mechanism 7. The guide hood 4 is made hollow with itsone end secured to one side of the planar roof 31 facing to the pedestal1, and the other end is extending towarsrds the pedestal 1. The parallelspatial linkage mechanism 5 formed of three straight feeding moldingdies 51 parallelly in connection with a base 54 is installed in theguide hood 4. All of these straight feeding molding dies 51 arerotatably hinged to the base 54 at mutually different positions thereof.By these three straight feeding molding dies 51 in connection with thebase 54 respectively at different positions, the base 54 can make linearmotion along Z axis direction, and also make at least two dimensionalswiveling around A and C axes shown in FIG. 4. The refining molding unit6 is installed on a side surface of the pedestal 1 facing to a sidesurface of the working platform 2. The feeding shaft mechanism 7 is fordriving aforesaid sliding slots 21,311 and 312 on the planar roof 31 andworking platform 2 so as to couple them with the linear guide ways 11,324 and 334 thereby making uni-dimensional (X axis or Y axis) linearmotion. As for driving means for planar roof 31 or the working platform2 with the feeding shaft mechanism 7, a ball screw driving mechanism 71employing a screw bolt 712 and its driving servo motor 711, or an oilpressure driving mechanism 72 for controlling an oil pressure circuit721 to drive a transmission rod 723 with an oil pressure cylinder 722,is applicable to move the planar roof 31 or the working platform 2.Referring to FIGS. 4(A) and 4(B), the controller 8 is for controllingand coordinating the operation of the straight feeding molding dies 51of the parallel spatial linkage mechanism 5 and the feeding shaftmechanism 7 so as to change the spatial azimuth of the base 54 therebyadjusting the relative position between the refining molding unit 6 andthe working platform 2.

[0024] Referring again to FIG. 4, each straight feeding molding die 51in the parallel spatial linkage mechanism 5 (herein referring to asingle molding die 51, should there be a plurality of straight feedingmolding dies, they are similarly constructed) includes a linear guideway 511, a sliding base 512, and a connecting rod 513. The linear guideways 511 are parallelly disposed with a relevant separation along theinner surface of guide hood 4. the connecting rods 513 are conjoined tothe circumference of the base 54 at different positions equallyseparated. The sliding bases 512 can move linearly along the linearguide ways 511 in the directions Z1 axis, Z2 axis, and Z3 axis shown inFIG. 4. Each connecting rod 513 is hinged to the sliding base 512 withits one end so as to be able to make at least uni-dimensional swiveling,while its other end thereof also can be rotatably hinged to the base 54.By connecting the connecting rods 513 of three straight feeding moldingdies 51 to the base 54 at different positions, and coupling respectivesliding bases 512 with their corresponding linear guide ways 511 forperforming linear motion, the base 54 is able to carry outuni-dimensional linear motion (Z axis direction), and two-dimensional(A/C axes) swiveling, three-dimensional motion altogether. As for theway the straight feeding molding die 51 driving the sliding base 512 tomove linearly along the linear guide way 511 for driving the planar roof31 or the working platform 2, a ball screw mechanism 52 (ie a servomotor 521 for driving a screw bolt 522), or an oil pressure drivingmechanism 53(ie. An oil pressure circuit 531 to drive a transmission rod533 with an oil pressure cylinder 532) is applicable as shown in FIGS.4(C) and 4(D).

[0025] How to make a hinged joint between the connecting rod 513 and thesliding base 512 will be illustrated as follows. A hinge pin 514 isformed at one end of the rod 513, while a corresponding bearing 515 isformed on the sliding base 512 such that the other end of the connectingrod 513 is able to make uni-dimensional revolution with respect to thejoint made on the sliding base 512 as a fulcrum. Meanwhile the joint ofthe connecting rod 513 to the base 54 can be carried out with auniversal shaft coupling 516. The universal shaft coupling 516 iscomposed of two units of shaft and bearing with an intersected center ofaxes. With this structure, the base 54 is able to make at leasttwo-dimensional swiveling motion with respect to the jointed point ofthe rod 513 with the base 54 as a fulcrum. Alternatively, a ball jointmay be employed which may serve equivalently as the above mentioneduniversal shaft coupling 516.

[0026] Referring back to FIG. 2 and FIG. 4, the parallel spatial linkagemechanism 5 is composed of three sliding bases 512 capable of straightlymoving up and down, the connecting rods 513 hinged to each base 512, therefining molding unit 6 and three universal shafts joint 516 interposedbetween the refining molding unit 6 and the connecting rods 513. Whenthree sliding bases 512 removes with different speeds or in differentdirections (Z1,Z2, and Z3), the refining molding unit 6 makes aspatially biased revolution due to swiveling of the universal shaftjoint 516 in A/C axes. The controller 8 controls the working information(such as a working position and suppling cutter tools etc.) to betransmitted to the planar roof 31 and the working platform 2 through thefeeding shaft mechanism 7 such that the refining molding unit 6 makestwo dimensional spatial directional change on X and Y planes withrespect to the working piece 9. In case the controller 8 furthercontrols the parallel spatial linkage mechanism 5 to carry out controlin Z axis (the same amount of displacement or speed of the sliding base512 at Z1,Z2 and Z3 axes directions) and in A/C axes (the differentamount of displacement or speed), the refining molding unit 6 will makea biased revolving motion in vertical (Z axis) and A/C axes directionwith respect to the working piece 9. In this version, the gantry typehybrid parallel linkage five-axis machine tool of the present inventionis able to perform refining the working piece 9 at least from fivespatial directions.

[0027] Referring to FIGS. 5 and FIG. 6, an illustrative view in ansecond embodiment, and an illustrative view in an third embodiment ofthe present invention respectively. In these two embodiments, the aspectof the pedestal 1, working platform 2, the machine framework 3 and theguide hood 4 are modified so as to improve the effectiveness of theparallel spatial linkage mechanism 5 when it is combined with the abovementioned component. As shown in FIG. 5, a working platform 2 a on amachine framework 3 a is secured to one furface of a pedestal 1 a. Eachof the end portions 321 a and 331 a of two supporting columns 32 a and33 a is parallelly fixed to two sides of the pedestal 1 a respectively,while each of the end surface 323 a or 333 a of the other end portions322 a and 332 a of the two supporting columns 32 a and 33 a isrespectively provided with a linear guide way 324 a or 334 a to becoupled with sliding slots 311 a or 312 a formed on a planar roof 31 aso that the planar roof 31 a can make uni-dimensional linear motion in Yaxis direction. And, on the other surface of the planar roof 31 a wherethe sliding slots 311 a and 312 a being formed, there are provided withtwo linear guide ways 34 and 35. These two linear guide ways 34 and 35and the other tow linear guide ways 324 a and 334 a on the supportingcolumns 31 a form projection on the X and Y axes planes perpendicular toeach other. At the time the guide hood 4 a is separated from the planarroof 31 a, the two sliding slots 34 a and 35 a which being formed on oneside of the originally stationary planar roof 31 a may couple with thetwo linear guide ways 34 and 35 on the planar roof 31 a. With thisstructure the guide hood 4 a is allowed to make uni-dimensional motionin X axis direction. The above mentioned combination may furthermodified in an third embodiment as shown in FIG. 6. Here, the planarroof 31 a and two columns 32 a and 33 a of the machine framework 3 a areintegrally made into one piece to form a ∩ shoped machine framework 3 b,while other two linear guide ways 11 b are formed on one surface of apedestal 1 b facing to ∩ shaped machine framework 3 b. The two linearguide ways 11 b and the two linear guide ways 34 and 35 originallyformed on the planar roof 31 a make projections on X and Y axes planesperpendicular to each other. Therefore, by coupling additional twosliding slots 21 b formed at the bottom of the working platform 2 b withthe two linear guide ways 11 b formed on the pedestal 1 b, the workingplatform 2 b is able to make uni-dimensional linear motion in X axisdirection.

[0028] It emerges from the description of the above embodiments that theinvention has several noteworthy advantages, in particular:

[0029] (1)Replacing the shaft head of a gantry type five-axis machinetool with a parallel spatial linkage mechanism does not accumulateerrors of all driving shafts as that is experiences in the conventionalmachine tools, on the contrary, it has the effect of balancing thegeometrical errors so as to easily achieve high precision effect andbring up the performability for refining complicated curved surface.

[0030] (2)The longitudinal stress is mostly alleviated by the drivingshaft so that the rigidity of the machine is intensified.

[0031] (3)Well designed thermal symmetric structure contributes tominimizing thermal deformation.

[0032] (4)By reason that the parallel mechanism structure is essentiallyfor withstanding most of the longitudinal stress, its loading capabilityis stronger than a serially constructed machanism with superior rigidityand less errors.

[0033] (5)The production cost of the present invention is less expensivethan that of a conventional five-axis machine tool so that the machinetool of the present invention will command a superior competitiveness inthe future market.

[0034] It is therefore to be understood that the above and othermodifications and changes may be readily made in the construction andarrangement of elements comprising the preferred and modified forms ofinvention without departing form the spirit and scope of the inventionas defined by the appended claims and reasonable equivalents thereof.

What is claimed is:
 1. A gantry type hybrid parallel linkage five-axismachine tool comprising: a pedestal having at least two parallel linearguide way provided at one surface thereof; a working platform having atleast two sliding slots provided at one surface thereof facing to saidpedestal such that said working platform being able to make a straightlinear motion with respect to said pedestal; a machine framework atleast composed of a planar roof and two supporting columns, the endportions of said supporting columns being parallelly fixed to both sidesof said pedestal, and the surfaces of the other two end portions eachbeing provided with a linear guide way respectively, besides, a slidingslot is formed at each side of said planar roof such that said planarroof is able to make straight linear motion with respect to said twocolumns by coupling said two sliding slots with said two linear guideways on the other two end portions; a parallel spatial linkage mechanismformed of a plurality of straight feeding molding dies parallelly inconnection with a base, all of these straight feeding molding dies arerotatable hinged to said base at mutually different positions thereof,by these straight feeding molding dies, said base can be driven to makeat least two-dimensional swiveling; a refining molding unit installed ona side surface of said pedestal facing to a side surface of said workingplatform; a feeding shaft mechanism for driving aforesaid sliding slotsso as to couple them with said corresponding linear guide ways therebymaking uni-dimensional linear motion; and a controller for controllingand coordinating the operation of said straight feeding molding dies ofthe parallel spatial linkage mechanism and said feeding shaft mechanismso as to change the spatial azimuth of said base thereby adjusting therelative position between said refining molding unit and said workingplatform.
 2. The machine tool of claim 1, wherein each straight feedingmolding die further including a linear guide way, a sliding base, and aconnecting rod, said sliding base is able to make a linear motion alongsaid liner guide way, and one end of said connecting rod is hinged tosaid sliding base, and can perform at least uni-directional swiveling,while the other end of said connecting rod is also rotatably hinged tosaid base, by connecting each said connecting rod of the plurality ofstraight feeding molding dies to said base at respectively differentposition and coupling each said sliding base with its correspondinglinear guide way for performing linear motions, said base is able tocarry out uni-dimensional linear motion (Z axis direction), andtwo-dimensional (A and C axes) swiveling, ie. Three-dimensional motionaltogether.
 3. The machine tool of claim 1, wherein said linear guideways of the plurality of straight feeding molding dies in said parallelspatial linkage mechanism are fixedly formed in the housing of a guidehood whose one end is secured to one side of said planar roof facing tosaid pedestal, and the other end is extending towards said pedestal. 4.The machine tool of claim 2, wherein said linear guide ways of theplurality of straight feeding molding dies in said parallel spatiallinkage mechanism are fixedly formed in the housing of a guide hoodwhose one end is secured to one side of said planar roof facing to saidpedestal, and the other end is extending towards said pedestal.
 5. Themachine tool of claim 2, wherein a hinged joint between said connectingrod and said sliding base is made of a hinged pin formed at one end ofsaid rod while a corresponding bearing is formed on said sliding basesuch that the other end of said connecting rod is able to make at leastuni-dimensional revolution about said joint made on said sliding base asa fulcrum.
 6. The machine tool of claim 2, wherein a hinged jointbetween said connecting rod and said sliding base is made of a universalshaft coupling composed of two units of shaft and bearing unit with anintersected center of axes, with this structure, said base is able tomake at least two-dimensional swiveling motion with respect to thejointed point of said rod with said base as a fulcrum.
 7. The machinetool of claim 2, wherein a hinged joint between said connecting rod andsaid sliding base is made of a ball joint such that said base is able tomake at least two-dimensional swiveling motion with respect to thejointed point of said rod with said base as a fulcrum.
 8. The machinetool of claim 1, wherein there are three straight feeding molding unitsin said parallel spatial linkage mechanism whose linear guide ways aredisposed paralled and equally spaced with each other in the housing ofsaid guide hood, and the three connecting rods of said parallel spatiallinkage mechanism is fixed to the circumference of said base equallyaparted at different positions.
 9. The machine tool of claim 1, whereinsaid refining molding unit is a cutter shaft with cutter tools attachedto its one end for cutting and refining a working piece gripped on saidworking platform.
 10. The machine tool of claim 1, wherein saidpedestal, said working platform, said machine framework, and said guidehood are assembled in another form when combining with said parallelspatial linkage machanism, ie. said working platform is secured to onesurface of said pedestal, each of the end portions of said twosupporting columns is parallelly fixed to two sides of said pedestal,while each of the end surfaces of the other two end portions of said twosupporting columns is respectively provided with a linear guide way tobe coupled with its corresponding sliding slot formed on said planarroof so that said planar roof can make uni-dimensional linear motion inY axis direction, and on the other surface of said planar roof wheresaid sliding slots being formed, there are provided with two linearguide ways, these two linear guide ways and the other two linear guideways on said supporting columns form projections on the x and Y axesplanes perpendicular to each other, at the time said guide hood 4 a isseparated from said planar roof, the two sliding slots which beingformed on one side of the originally stationary planar roof may couplewith said two linear guide ways on said planar roof so that said guidehood is allowed to wake uni-dimensional motion in X axis direction. 11.The machine tool of claim 10, wherein said planar roof and said twosupporting columns of said machine framework are integrally made intoone piece to form a ∩ shaped machine framework, while other two linearguide ways are formed on one surface of said pedestal facing to said ∩shaped machine framework, the other two linear guide ways and the twolinear guide ways originally formed on said planar roof make projectionson X and Y axes planes perpendicular to each other so that by couplingadditional two sliding slots formed at the bottom of said workingplatform with the two linear guide ways formed on said pedestal, saidworking platform is able to make uni-directional linear motion in X axisdirection.
 12. The machine tool of claim 1, wherein a ball screwmechanism is employed by said feeding mechanism to drive all saidsliding slots to move along the corresponding linear guide ways.
 13. Themachine tool of claim 1, wherein an oil pressure mechanism is employedby said feeding mechanism to drive all said sliding slots to move alongthe corresponding linear guide ways.
 14. The machine tool of claim 2,wherein a ball screw mechanism is employed by said straight feedingmolding die to drive said sliding base to move along the correspondinglinear guide way.
 15. The machine tool of claim 2, wherein an oilpressure mechanism is employed by said straight feeding molding die todrive said sliding base to move along the corresponding linear guideway.